Objective: To evaluate refractive outcomes of myopic femtosecond LASIK at Siriraj Hospital, Thailand.
Material and Method: A retrospective study of patients who underwent femtosecond LASIK at SiLASIK center, Siriraj hospital, Mahidol University, Thailand, from April 2009 to April 2010 was conducted. All patients had completely normal preoperative eye examination. All LASIK procedures were performed using Intralase® femtosecond laser (Abbott Medical Optics Inc (AMO)) and VISX® star S4 excimer laser (AMO). Postoperative follow -up included visual acuity (ETDRS chart) and manifest refraction at 1 day, 1 week, 1 month and 3 months. The flap thickness was evaluated at 3 months using Visante® optical coherence tomography (OCT, Carl Zeiss Meditec).
Results: One hundred and twenty eight eyes of 64 patients were included in the study. Mean preoperative manifest refraction spherical equivalent (MRSE) was -5.47 + 2.28 diopters (range, -1.88 to -12.63 diopters). At 3 months post-operation, the MRSE was -0.26 + 0.39 diopters (range, + 0.25 to -2.00 diopters) and 95.31% were within + 1.00 diopter of intended correction. There was 98% of eyes achieved uncorrected distance visual acuity (UDVA) 20/40 or better and 73% achieved UDVA 20/20 or better. There was 31% of eyes gained one line and 15% lost 1 line of corrected distance visual acuity (CDVA). The mean error of flap thickness (difference between actual and intended central flap thickness) was + 0.23 + 1.77 μm for 120 μm flap setting and + 0.22 + 0.97 μm for 110 μm flap setting. The flap morphology was planar configuration.
Conclusion: Myopic femtosecond LASIK at Siriraj Hospital provided satisfactory refractive outcomes and high accuracy of the flap thickness.

Keywords: Refractive outcome, Myopia, Femtosecond LASIK, Thailand